Thanks to gnivler and Tlarhices for help.
I'd just tried
Code:
sudo mount /dev/cdrom /media/cdrom -o norock -o ro
but it doesn't work...
Here could be an answer of the reason :
Code:
dmesg | grep mount
[ 8258.102945] UDF-fs: Partition marked readonly; forcing readonly mount
[ 8279.374126] udf: bad mount option "norock" or missing value
[ 8333.641370] UDF-fs: Partition marked readonly; forcing readonly mount
And if you look in the man of mount, the norock option doesn't exist...
Perhaps, it's relevant now : my Linux is Ubuntu 8.04.
Here is my version of mount : mount (util-linux-ng 2.13.1)
In the AppDB part of the site someone has the same problem, so I post a reply and see...
But your new ideas will be welcome of course :-)